upgraded cookie-signature to 1.2.1

Author: IamLizu

package.json

@@ -33,7 +33,7 @@
     "content-disposition": "0.5.4",
     "content-type": "~1.0.4",
     "cookie": "0.6.0",
-    "cookie-signature": "1.0.6",
+    "cookie-signature": "1.2.1",
     "debug": "4.3.6",
     "depd": "2.0.0",
     "encodeurl": "~1.0.2",